Chemical properties and antioxidant activity of exopolysaccharides from mycelial culture of Cordyceps sinensis fungus Cs-HK1

Po Hong Leung, Shuna Zhao, Kwok Ping Ho, Jianyong Wu

Research output: Journal article publicationJournal articleAcademic researchpeer-review

165 Citations (Scopus)

Abstract

Exopolysaccharide (EPS) was produced in a mycelial liquid culture of the Cordyceps sinensis fungus, Cs-HK1, at a rate proportional to mycelial growth. The crude EPS isolated from the culture medium by ethanol precipitation contained 65-70% sugar and about 25% protein, suggesting that the EPS was composed of polysaccharide-protein complexes. It exhibited a wide molecular weight (MW) range from about 5 kDa to more than 200 kDa. The intrinsic viscosity as an index of average MW of EPS, increased during the period of rapid mycelial growth to 11.0 dL/g on day 5, and remained relatively stable between day 5 to day 8 (stationary growth period). Both infrared spectrometry of EPS and gas chromatography of acetylated EPS suggested that the EPS had a β-d-glucan backbone. The EPS showed moderate antioxidant activities with a Trolox equivalent antioxidant capacity of 35-40 μmol Trolox/g and a ferric reducing ability of plasma of 50-52 μmol Fe(II)/g.
Original languageEnglish
Pages (from-to)1251-1256
Number of pages6
JournalFood Chemistry
Volume114
Issue number4
DOIs
Publication statusPublished - 15 Jun 2009

Keywords

  • Cordyceps sinensis
  • Exopolysaccharides
  • Ferric reducing ability
  • Mycelial culture
  • Polysaccharide-protein complex
  • Radical scavenging

ASJC Scopus subject areas

  • Analytical Chemistry
  • Food Science

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